Introduce async websocket stop

components/esp_websocket_client/include/esp_websocket_client.h

@@ -215,6 +215,38 @@ esp_err_t esp_websocket_client_start(esp_websocket_client_handle_t client);
  */
 esp_err_t esp_websocket_client_stop(esp_websocket_client_handle_t client);
 
+/**
+ * @brief      Initiate an asynchronus stop of the WebSocket connection without
+ *             websocket closing handshake
+ *
+ * This API initiates a non-blocking asynchronus stop of ws client. This will
+ * close TCP connection later directly without sending close frames. This is
+ * method is similar to esp_websocket_client_stop() but does not block the calling
+ * task. It is required to then later periodically call
+ * esp_websocket_client_is_already_stopped() to find out when its done and to
+ * finalize the closing of the websocket client.
+ *
+ *  Notes:
+ *  - Cannot be called from the websocket event handler
+ *
+ * @param[in]  client  The client
+ *
+ * @return     esp_err_t
+ */
+esp_err_t esp_websocket_client_initiate_stop(esp_websocket_client_handle_t client);
+
+/**
+ * @brief      After an asynchronus stop was initiated, this method returns if it is done already.
+ *             If this method returns true, it also performed some final cleanup. It should then not
+ *             be called anymore unless esp_websocket_client_initiate_stop() is called again.
+ *
+ * @param[in]  client  The client
+ *
+ * @return
+ *     - bool if it is done or not
+ */
+bool esp_websocket_client_is_already_stopped(esp_websocket_client_handle_t client);
+
 /**
  * @brief      Destroy the WebSocket connection and free all resources.
  *             This function must be the last function to call for an session.